Digital Equipment StorageWorks UltraSCSI DS-BA370 Series, User Manual

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Introducing the UltraSCSI RAID Enclosure
Ultra SCSI RAID Enclosure 1–7
•
I/O modules
UltraSCSI RAID Subsystem
A subsystem is one or more departmental server cabinets or data center
cabinets with enclosures. Each subsystem requires a master enclosure with
an UltraSCSI controller installed. Installing one or two expansion
enclosures and connecting them with cables creates an expanded subsystem.
See Table 1–1 for the capacities of the various subsystems:
_____________________ Note ______________________
Not all array controllers support configurations with expansion
cabinets. Refer to the array controller documentation to verify
that your controller can support multiple cabinets.
________________________________________________
Table 1–1 UltraSCSI Subsystems Capacities
Enclosures SCSI Buses Disk Drives Total Disk Drives
1 6 24 24
2 6 24 48
3 6 24 72
EMU
The device that monitors the status of the UltraSCSI RAID enclosure to
include power, ambient (intake) air temperature, blower status, and so forth.
It also detects error and fault conditions, displays these conditions, reports
the conditions to the user and the array controller, and, in some cases,
implements corrective actions.
PVA
The UltraSCSI RAID enclosure assembly whose primary functions are as
follows:
•
Allows the user to select the enclosure UltraSCSI bus ID,
•
Enables the user to place the subsystem in a standby power mode
condition or return it to an operational status,